Downy mildew caused by Bremia lactucae is one of the most serious diseases affecting lettuce cultivation and, periodically, novel strains of Bremia able to overcome existing resistance emerge. Identifying novel sources for Bremia resistance is therefore of great interest for lettuce breeders.

The EVA Lettuce network, operating within the ECPGR European Evaluation Networks (EVA), established in 2019, has jointly evaluated accessions of lettuce wild relatives from network partners’ collections for resistance against Bremia lactucae. Nine fully resistant accessions were identified in duplicate lab tests performed at two locations and using the most recent Bremia strains. These wild lettuce accessions may serve as potential new sources for breeding of Bremia resistance in cultivated lettuce.

This public private partnership, made up of six breeding companies and seven genebanks or research institutes from eight countries, also works on evaluating cultivated lettuce (Lactuca sativa) conserved in European genebanks for agronomic traits in field trials across Europe. The data generated using standard protocols will add to our knowledge on the adaptation of lettuce landraces/varieties to different climates and will be included in the European Search Catalogue for Plant Genetic Resources (EURISCO).

The EVA networks have been established with the support of the German Federal Ministry of Food and Agriculture, who is funding the project with €900,000 until 2023. For more information on the EVA Lettuce Network visit the website at: https://www.ecpgr.cgiar.org/european-evaluation-network-eva/eva-networks/lettuce.